ive used allmix for over a year now m8 , you wont need to add anything during veg as long as you pot up correctly ,, E.C is for hydro so dont worry bout that ,,, start adding ya nutes when ya go into flower

as long as ya water is between 6.4 and 7.5 before you add nutes then the all mix will have no problem buffering it , i use straight tap water ,bout 7.5 ph once ive added nutes it brings it down a bit but as long as ya tap water is drinkable itll be ok to use straight